Paul McGowan / PS AUDIO
It doesn’t take long to figure out the importance of AC power, and perhaps no device can better demonstrate the advantages of perfect AC than a Power Plant.
I wonder how many of the thousands of Power Plant owners across the globe really understand what’s important in power—why their AC regenerators make such a huge improvement to the sound of their system.
Is it clean power? After all, Power Plants lower distortion by several magnitudes: 2% to 5% THD becomes 0.2% THD. That’s not nuthin’.
Or is it perhaps something else?
It is the something else I’d like to focus on.
Back in the 1990s, when I started working on the problems of AC power, the focus was twofold: cleaning up the AC line noise and doing so without adding much in the way of impedance.
When the first waves of line conditioners and cleaner-upper AC filters hit the market, we could hear what we thought was better sound—certainly cleaner sound. Over time we felt the music had been cleaned too much—stripped of more than just noise—there was an unwelcome sterility to what we were hearing. That’s when we realized the filter’s increase in impedance was wreaking sonic havoc.
We had known for many years that lowering impedance dramatically impacted sound quality, but until those line filters came out, we’d never really put two and two together. The more we played and experimented, the more we became convinced that the lower the impedance the better the sound—to the point where we stopped worrying about removing unwanted AC noise.
That’s when the idea of the Power Plant AC regenerator surfaced. A well-designed regenerator regulated the AC power. What’s that mean? Regulation means that regardless of the power demanded by the connected audio equipment, the output AC voltage would never vary. A steady 120/230 volts regardless of demand—something that simply does not happen when you power equipment straight from the wall—and something made much worse by the insertion of an AC filter.
Not so coincidently, the act of voltage regulation proportionally lowers impedance: the tighter the regulation, the lower the impedance.
Regulating the AC power to a few millivolts of change regardless of the demand from your equipment is the key to the Power Plant’s success and why no equipment in the stereo chain—in particular power amplifiers—should be powered directly from the wall.
Cleaning the noise from the AC line? Turns out not to be so important.
It’s all about the regulation.